In early evening, why sometimes does the moon look larger in the sky when it's just above the horizon?

Answer 1

It's an optical illusion. When the Moon is low on the horizon, we can easily compare its size with the size of familiar things like trees and buildings, while when it is high in the sky we can't compare it as easily.

To prove this to yourself, the next time you see the Moon, hold your pinky finger up at arms length to "cover" the Moon, and you'll notice it covers the Moon quite easily. Make a mental note of the size of your little finger compared to the size of the Moon. Now the next time you see the Moon look huge along the horizon, do the pinky thing again, and you'll notice it's really the same size as before.

Answer 2

It may be hard to believe, but the moon is exactly the same size when it is near the horizon as when it is overhead. When we look at objects we are using our eyes which of course are connected to a brain, which means that how we view the world around us is subjective rather than objective.

When the moon is near the horizon, there may well be buildings or perhaps trees in the same line of sight, this makes the moon appear larger in angular diameter than when higher in the sky, as there are no land based objects to compare with the moon when it is further up in the sky.

Dr R. Loader

Answer 3

It's just an illusion. It looks bigger because you can see it in reference to the things on the horizon like trees houses and other buildings. When the moon is higher in the sky, it's still the same size, but since it's not next to anything, it doesn't look as big.

It's like seeing a basketball player by himself - nothing really special. Then stand him next to an average sized person, and he looks huge! It's all on point of reference because you are comparing one thing to another.

Answer 4

It's an optical illusion, the moon appears larger because it appears near objects on earth and you get a reference point. When it's high in the night sky you have nothing near it to compare it with.

Answer 5

The atnosphere is thicker when looking at the horizon, thus distorting the appearance of bodies like the sun and the moon.

Answer 6

Optical illusion. Near the horizon, you have things to compare it with. (This question has appeared here before.)

Answer 7

It's an optical illusion...the first 2 answers cover what I was going to say!
Try the legs thing, it works!

Answer 8

Could it be on an oval shaped orbit,and maybe closer to earth as it rises,and when it is at its high it is further away. We cant all be having an optical illusion.

Answer 9

Because when it's up high in the sky, there is nothing around it so it just seems smaller.

Answer 10

i've always wanted to know too apparently if you look up at the moon through your legs apart it looks 'normal' i can't say i've tried it though